The present invention relates to synthetic-grass structures and regards more specifically the removal of synthetic-grass structures.
A synthetic-grass structure of the above type is known, for example, from EP-A-1 158 099.
Basically, a synthetic-grass structure of the type referred to above comprises, in normal laying conditions, a sheet substrate with a plurality of filiform formations that extend upwards starting from the substrate itself so as to simulate natural-grass cover or natural turf. A particulate filling material or infill is dispersed between the filiform formations so as to maintain them in a substantially erect condition.
The solution described in the document cited above specifically envisages that the aforesaid filling material or infill should consist of a substantially homogeneous mass of a granular material chosen in the group made up of polyolefin-based materials and vinyl-polymer-based materials.
In other solutions, such as the one described in U.S. Pat. No. 5,958,527, instead, the infill comprises a plurality of layers of granular material, such as sand, fragmented rubber material, obtained for example as material recycled from used tyres, and/or mixtures of the two.
The synthetic-grass structures are increasingly considered as being a valid alternative to natural-grass cover. This, in particular, regards applications (sports facilities, etc.) in which, for different reasons (environmental conditions, intense use, etc.), upkeep of natural turf proves to be a critical problem, also on account of the maintenance costs involved.
Prolonged exposure to environmental agents (light, atmospheric agents of various nature, etc.) renders it, however, necessary to replace the synthetic-grass cover at intervals in the region of, for example, 4-12 years.
The operation of replacement involves pulling up the synthetic-grass flooring that was previously laid and the consequent gathering-up and disposal of the corresponding components.
This applies chiefly as regards the sheet substrate and the filiform formations which simulate natural grass. In many cases, the same considerations apply, however, also to the filling materials, above all in the case where the infill was initially distributed in a number of superimposed layers of different materials, which are inevitably bound to mix together during use and even more during the operation of removal of the flooring.
The purpose of the present invention is to enable the removal of synthetic-grass floorings to be carried out in conditions that make possible a high degree of re-use of the materials that make up the synthetic-grass flooring that is pulled up in order to be able to lay a new synthetic-grass flooring. The possibility of salvaging and re-using the material is significant both in economic terms and in environmental terms if it is taken into account that synthetic-grass floorings are currently widely used for sports facilities, such as soccer fields, rugby fields or American-football fields, in which the surface of the synthetic-grass floorings may measure even several thousand square meters in area.
In accordance with the present invention, the above purpose is achieved thanks to a process having the characteristics recalled specifically in the ensuing claims. The invention also regards the corresponding use and the corresponding product of the salvaging operation.
Essentially, the solution according to the invention is based upon the recognition of the factxe2x80x94an altogether unexpected and surprising onexe2x80x94that the particulate material obtained from shredding of the sheet substrate and filiform formations of a synthetic-grass flooring that needs to be pulled up can be used to advantagexe2x80x94either completely or in partxe2x80x94as particulate infill made of plastic material according to the criteria set down in EP-A-1 158 099 already cited previously. This is true even if the synthetic-grass flooring that is pulled up has been exposed to environmental and atmospheric agents for a prolonged period of time, i.e., in the region of the time intervals involved in the change of synthetic-grass floorings referred to previously.